THE CODE2 FOR SENSORS FOR DOMESTIC ROBOT......

//THE CODE2 FOR SENSORS FUNCTIONING
// lowest and highest sensor readings:

const int sensorMin = 0;     // sensor minimum
const int sensorMax = 1024;  // sensor maximum
int val = 0;
#define led 13
#define l1  11
#define l2  8
#define buz 10
const int buzzerPin = 9;
const int songLength = 18;
int tempo = 113;
int beats[] = {1,1,1,1,1,1,4,4,2,1,1,1,1,1,1,4,4,2};
char notes[] = "cdfda ag cdfdg gf "; // a space represents a rest
void setup() {
  // initialize serial communication @ 9600 baud:
 
pinMode(buzzerPin, OUTPUT);

  Serial.begin(9600);
  pinMode(led, OUTPUT);
}
int frequency(char note)
{
  // This function takes a note character (a-g), and returns the
  // corresponding frequency in Hz for the tone() function.

  int i;
  const int numNotes = 8;  // number of notes we're storing

  // The following arrays hold the note characters and their
  // corresponding frequencies. The last "C" note is uppercase
  // to separate it from the first lowercase "c". If you want to
  // add more notes, you'll need to use unique characters.

  // For the "char" (character) type, we put single characters
  // in single quotes.

  char names[] = { 'c', 'd', 'e', 'f', 'g', 'a', 'b', 'C' };
  int frequencies[] = {262, 294, 330, 349, 392, 440, 494, 523};

  // Now we'll search through the letters in the array, and if
  // we find it, we'll return the frequency for that note.

  for (i = 0; i < numNotes; i++)  // Step through the notes
  {
    if (names[i] == note)         // Is this the one?
    {
      return(frequencies[i]);     // Yes! Return the frequency
    }
  }
  return(0);  // We looked through everything and didn't find it,
              // but we still need to return a value, so return 0.
}
void tony()
{
  int i, duration;

  for (i = 0; i < songLength; i++) // step through the song arrays
  {
    duration = beats[i] * tempo;  // length of note/rest in ms

    if (notes[i] == ' ')          // is this a rest?
    {
      delay(duration);            // then pause for a moment
    }
    else                          // otherwise, play the note
    {
      tone(buzzerPin, frequency(notes[i]), duration);
      delay(duration);            // wait for tone to finish
    }
    delay(tempo/10);              // brief pause between notes
  }

  // We only want to play the song once, so we'll pause forever:
  while(true){}
  // If you'd like your song to play over and over,
  // remove the above statement
  }
void flamesensor() {
  // read the sensor on analog A0:
  int sensorReading = analogRead(A0);
  // map the sensor range (four options):
  // ex: 'long int map(long int, long int, long int, long int, long int)'
  int range = map(sensorReading, sensorMin, sensorMax, 0, 3);

  // range value:
  switch (range) {
    case 0:    // A fire closer than 1.5 feet away.
      Serial.println("** Close Fire **");
      digitalWrite(l1,HIGH);
      tony();
      break;
    case 1:    // A fire between 1-3 feet away.
      Serial.println("** Distant Fire **");
      digitalWrite(l2,HIGH);
      tony();
      break;
    case 2:    // No fire detected.
      Serial.println("No Fire");
      break;
  }
  delay(1);  // delay between reads
}



void pir()
{
  val = digitalRead(3);
  if (val == HIGH) {
    digitalWrite(led, HIGH);
    Serial.println("motion is detected");

  }
  if (val == LOW) {
    digitalWrite(led, LOW);
    delay(50);
    Serial.println("nothing is detected");
  }
}
void gassensor() {
    float sensor_volt;
    float sensorValue;

    sensorValue = analogRead(A1);
    sensor_volt = sensorValue/1024*5.0;

    Serial.print("sensor_volt = ");
    Serial.print(sensor_volt);
    Serial.println("V");
    delay(1000);
}
void loop()
{
  gassensor();
  flamesensor();
  pir();
}